First you must have the photo/object that you want to upload (Read the Forum Rules to make sure it is appropriate).Then if you have a photo bucket account or other things like that you can use that. I am going to show you how to use the "servimg" one.To use it, click on the "Host an image button"

Then you should see a box like this.

Log in with your forum account password and E-mail and it should look like this.

Then click "Browse"

Then select the photo you want to show.

Then press the "Host it" button. Then copy the bottom link.

Then press the servimg button again to exit out of it, then press the Insert image button.

Then past the image link that you copied and paste it in that box and you have it!